1. Field of the Invention
This invention relates to an exchangeable unit steam trap, and more particularly to a steam trap capable of easily exchanging its trap unit according to used conditions, for example, set drain temperatures or easily replacing its trap unit with a new one for repairing.
2. Description of the Prior Art
Various kinds of steam traps have been used. For example, there has been proposed a steam trap using a wax mixed with metal powder whose thermal expansion causes a valve in the trap to open and thermal contraction due to relatively low temperature drain water opens the valve. In general, with such a steam trap, a temperature at which condensate or condensed water is exhausted is determined by a performance of a thermoelement for example thermowax assembly incorporated in a trap unit of the steam trap. This hitherto used steam trap is, however, complicated in construction which could not rapidly adapt itself to variations in used condition and is difficult to replace its trap unit with a new one for repairing.
There has been also proposed a steam trap whose draining temperature is adjustable by rotating an adjusting screw by means of a screw driver after a removal of a cap of the steam trap. With this steam trap, however, the adjustment of the draining temperature requires great skill and is difficult to replace its trap unit for repairing.